I’d like to point out that two years ago, I wrote a program that uses the Strava heatmap to detect missing paths in OSM. This program enables the creation of MapRoulette challenges to incorporate these paths into OSM.
You can read all about it in my diary: @jcr83/diary/402938.

Hi Luzandro, I know that there are many false positives near sport centers, but sometimes they are real issues, because the “leisure=track” is missing. About the tasks database: In early versions, only one missing way per strava tile was detected, so if there was a false positive, other missing ways could not be detected. But I improved the algorithm, and now several missing ways can be detected in a single tile. So I have have to check if the database is still useful.

No ! See osm.wiki/Strava#Data_Permission_-_Allowed_for_tracing!

Hi Binnette, I just started to wriite this article, it is not finished !

Broadcom has announced a new GPS receiver chip (BCM4775X) that uses two frequency bands. They claim a 30 cm precision. See: https://www.broadcom.com/products/wireless/gnss-gps-socs/bcm47755/

If true, this precision would be good enough for OSM.